Potential of the point in the origin

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Discussion Overview

The discussion revolves around finding the electric potential at the origin due to a charged line along the x-axis, with the reference point at infinity. Participants explore different methods of integration and the implications of the potential being well-defined.

Discussion Character

  • Homework-related
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant suggests using the formula V=∫dV and expresses uncertainty about integrating with respect to the line charge.
  • Another participant proposes integrating along the line from -a to a, but questions the well-defined nature of the potential.
  • A participant calculates the potential as V=Q'2a/4πε0r but expresses doubt about the correctness of this result.
  • Concerns are raised about the potential diverging, which may affect the ability to compute it accurately.
  • One participant asserts that the potential at the origin is infinite, suggesting the assignment may be impossible.

Areas of Agreement / Disagreement

Participants express differing views on whether the potential is well-defined, with some suggesting it diverges and others attempting to compute it. There is no consensus on the validity of the calculations or the nature of the potential.

Contextual Notes

Participants highlight the potential divergence of the integral and the implications for defining the potential at the origin. The discussion includes uncertainty about the integration process and the meaning of variables involved.

Who May Find This Useful

Students and educators interested in electrostatics, particularly in understanding the challenges of calculating electric potentials in certain configurations.

cdummie
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Homework Statement


Find the potential of the point in the origin in regard to referring point at infinity if there's charged line laying on x-axis as shown in the picture.

Screenshot_1.png


Homework Equations

The Attempt at a Solution



I know two ways to find a potential:

V=∫dV and V=∫E*dl

using first formula i have dv=dQ/4πε0r and i have Q=Q'dl but i don't know how to integrate that, i mean i have dl and i don't know what to do next.
 
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Integrate along the line from -a to a?

I don't think the potential is well-defined, however.
 
mfb said:
Integrate along the line from -a to a?

I don't think the potential is well-defined, however.

When i integrate from -a to a i get V=∫dQ/4πε0r=Q'/4πε0∫dl since ∫dl=2a i get V=Q'2a/4πε0r but this seems way to easy, so I am not sure is it correct.
I don't know what you mean, i have to find the potential at point B(0,0) and referring point is at infinity. That is how it's defined.
 
Setting up the integral is easy.
cdummie said:
I don't know what you mean, i have to find the potential at point B(0,0) and referring point is at infinity. That is how it's defined.
Yes, but you cannot do this if the integral diverges.
 
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cdummie said:
When i integrate from -a to a i get V=∫dQ/4πε0r=Q'/4πε0∫dl since ∫dl=2a i get V=Q'2a/4πε0r but this seems way to easy, so I am not sure is it correct.
what is r?
I don't know what you mean, i have to find the potential at point B(0,0) and referring point is at infinity. That is how it's defined.[/QUOTE]
what mfb means is the potential at the origin is infinity. You have been given an impossible assignment!
 
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